The Bulls or any pro team, as dumb as the Bulls have been, aren't going to just bench someone to set them up for a 6MOTY award. LaVine is starting because #1, the management concept of selling and buying in, which means they made the move and have to prove to the fans he was worth trading Butler and getting fans to fall in line somehow. #2, the Bulls don't have the depth chart to put LaVine anywhere else. #3, because the Bulls are in a rebuild with low risk, low pressure, it doesn't hurt them to throw minutes and match-ups at players they want to develop. Lastly #4, along with the trade, they need to justify the massive contract.
Now he should develop further. Never said he couldn't. Don't fail in comprehension here and confuse two concepts. One concept is that he wont develop more at all, and the other is that he wont develop enough. It's not just Zach's work and development that goes into this, but every other player in the league that he is competing with, along with the attrition of young players in the same argument still in school or overseas that share the very same data points. I use the word attrition, because Zach's skills are built around him being young and agile, so his strengths are competing with the younger half of elite basketball players, not the older...as HE gets older. So that is a ship sailing away slowly as he too goes from early 20's to late 20's. His athleticism and work ethic to stay elite at his level is going to naturally conflict with his effort to round out his game. How do we know that is likely the case? Every example historically of an undersized 2 guard in NBA history that failed to round out their game enough in the first 5 seasons of their career in a similar position has reached the same fate as a *starter* but flourished as a 6th man if and when those players were on teams built for that type of 6th man, and if and when those players could wrap their brain around the concept of not starting and seeing the value of allowing a good coach to put them in their best role for TEAM success, and not just individual success(yay mom, look at stats, whoopdy doo).